As usual I agree with Globalti. I've had rigid, hardtail, short FS and 6" FS bikes (in addition to my road bike).
Rigid MTBs were all there was in the old days. It made you learn a lot about picking lines and weight distribution. They cost loads less to buy (unless you go for a Jones Ti frame!), less to maintain, and generally weigh less, and go wrong less often. But you get shaken to pieces on the sort of trails that seem to be normal now. Of course, nowadays most people are at least on a hardtail, which to be fair for most purposes is probably best. I've seen many a good HT rider embarrass people on posh full sussers (probably including me!) A few of the guys I ride with are on HTs, and they keep up fine, (especially the more skilled ones) though I do keep hearing mutterings about their legs being tired from all the pummelling. A couple of them have switched to FS and have got quicker as a result, but it can get quite loose and rooty, with drop-offs and all sorts of bumps where we ride.
I now ride a Cannondale Jekyll with about 5-6" f&r. It makes up for a lot of suspect technical 'ability', and allows me to keep up much better than before. However, I did have to 'fork out' (sorry) for a shock service after a couple of years, which wasn't cheap.
For me it's a question of:
1 - budget
2 - back health (I suffer)
3 - the severity of the terrain. If it's gnarly enough, it could be worth going FS.
I wouldn't go back to a HT off-road now, though I still ride my old one on road as a winter hack.
FWIW one of our lads recently got a Trek Fuel and he's had a load of grief with his shock bushes (and paint coming off). Some bikes/suspension designs seem to suffer. I know all the arguments for Horst Links and 4-bar linkages vs unipivots (less bob etc) but these days, with Pro-Pedal and all that stuff, my Jekyll (unipivot) hardly bobs at all when properly set up, but the smaller bushes and bearings that you get in more complex designs do seem to cause a bit of trouble. Mine went in my old Rocky Mtn Element, and since getting the 'Dale I haven't looked back.
Hope that helps and doesn't throw you into disarray for casting doubt on the bike you were thinking of. They might not all have problems.