We are not using it because we are using our own intelligent index defrag script, but it is a great solution for those who are using the maintenance plans. Just be aware that there is a bug in Ola's script, or at least it used to be. If you have created a table that should have AUTO UPDATE STATISTICS turned off and you use his script to defragment indexes, when the index is reorganized (not rebuilt), then UPDATE STATISTICS is used without the NORECOMPUTE option. That will set the index to AUTO UPDATE STATISTICS. I know, you should have updated statistics for efficient query plans, but there are some cases when you can't afford the table to auto update and want to controll the updates manually. (but that is for advanced users and not for the accidential DBA)
I use Ola's defrag script. He is totally open to suggestions, I passed on a few things that sparked an interesting discussion with him. I think he even implemented one of them. So if you have an edge case he has not considered, let him know and he may well put it in.
EDIT Since I started at my current job, I use Ola Hallengren's scripts. In fact, my first real task at work was to implement them on our ~100 instances. I have customized them, so that they all run in one single job on the instance, and with configuration parameters for each database in a configurations table. /EDIT I am too using Michelle Ufford's script. I'm using it without any customizations. One thing about it, which may very well be a "by design" thing but that I find annoying, is that when it stops unexpectedly for some reason and you run it the next time, it still has its worktables partly loaded. I would prefer them to be cleared and reinitialized each time the proc runs. But to answer the question: No, I'm not using Ola's scripts. I probably would have, if I hadn't tested Michell Ufford's scripts first.
Yes I do. It's a good solution for me to install on my DBA-less clients, as it works, it is fully documented by Ola, it is supported, and once again it just works! I have added other processes around it, such as the clean up of files for databases that no longer exist, and I also think I'd like to control the list of excluded databases through a table (as well as on the command line), but regardless of that, it's one of the best backup utilities I have seen.
I am using the script on all my customers and it is working great, large or small customers. I customize the jobs for every customer since all of them have diffrent needs. Working as a consultant the most important part besides the customization is to train the DBA's that will use the solution and make it easy for them to set up the customized solution by themselves. Teach them how/where to modify parameters, look for logged errors and so on to make them comfortable with the solution.