If you are talking about pro trainer boards, then I have 2 thoughts on these.
1. If you are a high level player, then these boards are great for getting you to focus on your grouping.
2. If you are just an average pub player, then I think you can get disappointed by not hitting the triple and double very often.
I put myself in the 2nd category and I find that confidence plays a big part in my game. So the more I hit my target, the more I will keep hitting it. That is why I have been playing on my soft tip board a lot recently.