I have had a similar experience with both versions of the Peltor as well. First set I liked a lot but the manual tuner was a problem. That set eventually died of unknown causes.
I recently got the digital version with MP3 input. It's better but still not perfect. Tuning is much easier though it still suffers some static/poor reception. My biggest complaint is the MP3 input. All it does is override the radio so you have to have it tuned to a weak frequency. Seems I cannot get a clear MP3 signal. Also, like the OP I found there is no place for the MP3 player. I kept mine in my shirt pocket while mowing for ease of access but found all the dust got into the controls. It's ok, but I'm no longer using it on the tractor. Radio is fine anyway.
So, for radio I give it a 7 of 10, for MP3 I give it a 2 of 10. For noise control it get's a 9 of 10 and for comfort/ergonomics an 8 of 10. Overall, better than nothing for sure.