I'm using the hyperion at the moment, because my marines still need some training and I boarded til now (with 1.2) only M6 (nearly 70) and so I shortly interrupt the education for some marines with a high enough education for boarding M6 to board a bit and to advance their fighting skill, after a while they get replaced by others, when they reached the 100 fighting skill.
Boarding with the Hyperion is easy, because of the capacity for more than 5 Marines and with 6 Marines the boarding of M6 without losses is easier.
atm my favourite targets are the osprey (sold for more than 10Mio) and the Heavy Versions for a perhaps later personal usage.
Later (for the bigger Targets and 20 Marines) I'm going to board with the Tiger and two TP (Angel or Scabbard for their shields and their chance to survive a few hits). This combination worked fine in 1.1.