I used H&R block every year. It was working well in the past. Easy to use and pretty straightforward.
Unfortunately last time I used H&R Block I had a severe bug. I contacted the support by phone, email and Twitter but they didn't even replied to me. Finally after few days I switched to TurboTax.
If you use online tax preparation, it is user friendly. I think the overall product is as good as tax slayer, and tax act.
I have tried this more than one year and it continually does not give me as good of returns as other software.