I've been a Inmotion hosting customer for about a year now, and chose them only after VERY careful consideration of hosting environment options. I had previously used godaddy.com hosting, but there were too many reasons to leave, and I needed a host that met all of my needs.
1) php sendmail enabled
2) latest version of php (currently 5.2.6)
3) PEAR available
4) mod_rewrite available
5) .htaccess & php.ini customization allowed
6) multiple domains on one account ( I use 5, but they allow 6 )
7) unlimited disk space
8) unlimited bandwidth
9) MySQL databases ( I use 3 of 50 available )
10) phpMyAdmin available
11) Cron jobs available
Inmotion met all of my needs, and I have been satisfied with their service. I have noticed that there is some downtime, but I have experienced downtime with every host I have ever used, so I can't say anything too negative about that.
One thing that I like, is that compared to Godaddy or some of the other bigger hosts that I have used, Inmotion still has personalized "talk to a real person" phone support 24/7. This is a big bonus when I'm up at 3AM and can't figure something out.
There was one instance where one of the admins did an update to the server, and my PEAR got messed up. I want to keep this review as helpful and informational as possible. I still don't think I could find a better host. I am impressed and will keep using them.
Normal accounts that are purchased over the web are not able to use sendmail. I had to specially request that I be put on a server with sendmail enabled, but once I did, they did it immediately. They have always been very courteous, and I feel like I am getting an exceptional deal for $8.95 a month.
I would be surprised if anyone has anything bad to say about Inmotion hosting. If you are looking for a good host, you won't be disappointed with them unless you are very critical, and in that case you should probably be on a dedicated server or some type of managed hosting.
Thanks for reading my review, and I hope it helps you.