Good luck with using your 2-4-1 and as the rather flippant comment suggested earlier, your main obstacle will be finding availability to the destination of your choice (with a bonus of convenient dates!). "Choosing" the type of aircraft that might have the best seats might be a wish too far. Simply, the three moving parts are: dates, destinations (alined to destinations, type of airframe) and most importantly, availability. These all have to coincide! I hate to be negative about this but I have 'lost' more 2-4-1s than I've used, because I just couldn't find the availability. I am currently sitting on 350k plus of Avios and a 2-4-1 voucher, but can't get a booking to where I want to go, when I want to go there.