Hostmonster can be slow on shared accounts. I only use them 'cause somehow I can use very long domain names.
For everything else I do HostGator - very, very happy with them!
I also had support problems with H-Monster as they go for "do it yourself" approach and instead of live help they will send you to some written instructions.
On my accounts HostGator has everything latest installed so I never had any server conflicts, and always had an instant answer for me to the point, great help.
But that's just me, I've heard very little criticism for them comparing to other hosts.
I have only used Dreamhost, and I have to say, I've been pleased with them. I've hosted 60+ domains with them and they have kept me happy. You will always get what you pay for, and shared hosting isn't always the best, but if it gets the job done for you that's all that matters.
If you go with Dreamhost, you can use coupon code 15OFFDRM at Checkout for $15 off, haha.
I have been with Dreamhost about 5 months. Their customer service is good and they are a host that is serious in their business. I did encountered some down time issues. Some customers quite frustrated at that time, but Dreamhost takes the step to eliminated their down time problem. I think it is worth trying Dreamhost.