The Curve really isn't/wasn't made for HTML browsing, at least that's my opinion. That is why the screen is so small, if you want HTML browsing your best bet would be the Storm or Tour...
I actually use all three. I use the bb browser for checking my bank accounts, the opera browser for espn.com and my fantasy football stuff, and bolt for pretty much everything else!
Bolt- without a doubt!!! Sooo fast, and works great!
I'm in love with that Browser... I never have problems with it, so perfect! I use BB Browser on occasion when downloading things OTA though.
I use Bolt and the BB browser. I too tried Opera, but it did not load certain web pages as the Bolt browser. As stated earlier, try them both and who knows you may use all three!!
I have BOLT on my phone. I installed Opera Mini, this morning, and I went to crackberry on both browsers. I spent an hour flipping back and forth between the two. I find that Bolt is more "true" to the way the website looks on the desk top. There was some overlapping with OM with images and text that I did not like.
Now, there are some features that I do like about OM. I think it's a little quicker. I'm at work so i cant do into all the details but my suggestion is to download both and go to your favorites sites and see how both browsers function. Your decision will be based on which features/functions/layout you will like the best.
From the little bit of playing around I have done, OM hasn't made me switch from Bolt but I will continue to do this comparison for a few more days before I uninstall one of them.