merlin are the same as any other shop imo some good some bad days.
They sent me the wrong mech once, long cage rather than medium, not a big deal you might say but i could have got the long cage cheaper and specifically wanted a medium. I paid for next day delivery so i could be riding at the weekend. they then wouldn't send me out the right one until i had sent the other one back which mean't i couldn't sue my bike over the weekend. ended up going into Evans and buying one.
Also, I googled 'fox RP2' to see where comes up as cheapest and Merlin pops up, i go over to their site and they've sold out. This happens a lot. If it's not in stock don't tell me you have it!
Little things i know but it means i'm just not completely convinced about them. I have had great experiences with merlin as well though.