I have a hybrid approach. First, I look for an MS only solution. There's a tremendous number resources available thru SQL Server Central, other web sites and blogs that can answer many questions. We're fortunate to have such a rich ecosystem of experts, MVP's and other professionals that enjoy demonstrating their knowledge and helping fellow users.

After exhausting an MS only approach, I look into the tool vendors. Many of the tools available appear to consolidate build in features and make the existing features more accessible. I consider the reputation of the company and how their offering solves my need. I reach out to peers in the SQL community for their opinion on a specific product. I get unfiltered opinions about which products work and why.

I don't think I could do my job as easily without SQL Compare, SQL Data Compare, SQL Prompt and the refactor product. (shameless plug for Red-Gate). There are other tools I've used but won't mention because this shouldn't break into a diatribe of Product X is much better than Product Z.

I'm fortunate that if I can justify the tool then my boss is ready to make life easier for me. Having a supportive management structure is very welcome.