I've been looking at some of the Farecompare listings for Boston searching by ppm (http://www.farecompare.com/search/flyertalk.html?departure=BOS&fares=Both&carrierFilter=CO&filter=ALL&ppm=0.05&savings=99999&distance=0&sortby=ppm&p=1).

Some of these don't price out conveniently but BOS-MEX is doable as a one day turnaround leaving Boston at 5:30am and returning at 11:55pm the same day. Even better, it avoids EWR and the layovers at IAH seem reasonable even with the terminal change as I won't have much beyond a small backpack. I don't have lounge access for me although I could go buy a pass I suppose.

Two hours should be enough at MEX to re-clear customs and immigration from what I've read here. The really appealing part for me is that it can all be done in one day and will only cost me parking at Logan for the 24 hour period.

The cost isn't spectacular at 5.7cpm and 6.4cpm after you factor in Logan parking.

It prices out on days when I can actually travel. Buy or wait for something better?

Wait. When you search by PPM, you go by the straightest line between two points. While BOS-MEX is a long distance, something simpler might be a lot more advantagous. BOS-AMS :) Make sure you check DL, AS, AF, KL, VS, KE, NW fares etc. if you are collecting OnePass miles - its a slightly different mix for other SkyTeam partners. Additionally, check your surrounding airports. IIRC, Providence has some supercheap airfares.

There are many FlyerTalkers in the BOS area - hang tight and ask around when you spot one. There are a lot of better deals out there.

I'd have to concur...I'll only do Mexico/Central America trips if I make a trip out of it (maybe 3-4 days) and it's someplace I want to go. From a purely mileage-focused perspective the numbers don't tend to add up vs. transcons or other possibilities. Then add to that the extra taxes, and some of the airlines even have the nerve to do hefty "fuel surcharges" on trips like that! (Thankfully FC is rolling those in). There have been specials from time to time but I haven't been able to get the miles to add up.

I've been looking at some of the Farecompare listings for Boston searching by ppm (http://www.farecompare.com/search/flyertalk.html?departure=BOS&fares=Both&carrierFilter=CO&filter=ALL&ppm=0.05&savings=99999&distance=0&sortby=ppm&p=1).

Some of these don't price out conveniently but BOS-MEX is doable as a one day turnaround leaving Boston at 5:30am and returning at 11:55pm the same day. Even better, it avoids EWR and the layovers at IAH seem reasonable even with the terminal change as I won't have much beyond a small backpack. I don't have lounge access for me although I could go buy a pass I suppose.

Two hours should be enough at MEX to re-clear customs and immigration from what I've read here. The really appealing part for me is that it can all be done in one day and will only cost me parking at Logan for the 24 hour period.

The cost isn't spectacular at 5.7cpm and 6.4cpm after you factor in Logan parking.

It prices out on days when I can actually travel. Buy or wait for something better?
What airline are you looking at? (It helps to put the airline in the subject line.) And what is the fare, and what is the per day parking fee at Logan that it increases your overall costs by >10%. 5.7 cpm is too much to be of interest to me and I should think most MRers, unless it wasn't a pure MR like the one you are contemplating or we were already close to a mileage goal we wanted to hit. Even if you are getting a 100% mileage bonus, you will be earning miles at almost 3 cpm, which isn't too good from a value standpoint (unless perhaps you can use them for an F award to Australia or other distant point), and still less good when you are looking at >12 hours of flying in coach.

Like itsme said, give us a few more details.

In general though, the most eficient way to MR is to start by going up and down one coast, then across the country, up and down that coast, then home. Alternatively, take the long way to whatever destination looks cheap. For example, UA often has relatively cheap fairs from IAD/DCA-MIA. While its only about 1000 mile nonstop, by way of ORD it's 1800.

To clarify I'm gathering miles on CO. I have just over 25K EQM booked/flown through the beginning of May. I was halfway between silver and gold at the end of last year so I just left it alone. As a result I'm only earning a 50% mileage bonus currently as a lowly CO Silver. I'm trying to see if I want to go for gold this year and the 100% bonus.

I normally try to take the T to Logan but for some early morning flights or late evening arrivals I'd have to either drive or cab it. If I have to cab it both ways it may be cheaper to drive depending on how long I'll have to park. Rates are $22.00-24.00/day for the closer lots, $16/day for the economy lot. With a Fast Lane transponder tolls would cost me $4 round-trip. Taxi is about $30 each way. T is $1.70 each way on the subway with a Charliecard.

The specific fare I was looking at was all on CO metal, same-day turnaround: BOS-EWR-MEX-IAH-BOS for $277.10 all-in with reasonable layover times for 4936 EQM.

Since that flight leaves at 6:30am and arrives at 11:55pm I would need to take a taxi both ways or just drive and park for 24 hours which would add $20 in the economy lot. I think my initial calculations were a bit off but that works out to 5.6cpm without parking/tolls and 6.0cpm with parking/tolls.

Wish I could help with the CO specifics but I'm a UA guy.

In the end it's really up to you. I've done expensive MRs and I've done cheap ones. I personally value sleeping in my own bed (I don't do redeye MRs) more than I do saving a couple of tenths of a cent per mile.

For example, I've got a couple of IAD-LAX-LAS-SFO-IAD MRs (out at 6am, home around midnight) coming up this month. I could have squeezed in a couple of more segments and taken a redeye home but it's just not worth it to me.

My advice is to get out and fly.