My wife and I are going on a 22 night trip to europe. We haven't checked a bag in over ten years (including to australia) but we are going to four cities - Dublin, Rome, Copenhagen, Paris - and also a northern european cruise, so we are going to need to bring too much for our usual 20' carryons to handle.
We will be flying USAir, united, aer lingus, and scandanavia airlines and will need to cart the bags from metro to hotel, etc.
After my research I am down to two travelpro bags that are cheap but get decent reviews, don't want to invest in B&R as I doubt we will use them again for years.

Travelpro Walkabout Lite 4 29" Exp Spinner Upright
$154.99
Dimensions: 29" x 20.5" x 12"
Weight: 12 lbs, 8 oz

Travelpro Maxlite 2 25" Exp Spinner
$99.99
Dimensions: 18.5" x 11" x 25"
Weight: 8 lbs, 9 oz

Since I've only done carryon for my last 100 or so flight, I have no concept of weight and size and handling ability with these bags. I've never weighed a packed bag, so I don't know if getting the 29" is worthwhile if it will be overweight for these airlines if we fill it up? I know for instance that the aer lingus flight I booked has a 20 kg limit for checked bags, I think 10 euro more for 25kg, anything after that they pound you fee-wise.

Thoughts? Thanks so much in advance!