My experience: I treated myself to a trip to Lamu & Peponi after visiting good friends in Kenya, I'm very glad that I did. My experience was a good one, especially as a solo traveller - Carol and her team were very friendly and welcoming and I appreciated their consideration in making my brief stay enjoyable.
As Lamu, Peponi is unique and has its quirks but that is certainly part of the appeal, depending on the expectations that you do or don't arrive with. The rates were above what I ordinarily pay when travelling privately but I was not disappointed, I'm sure that you could find fault with Peponi if you wanted to but, as with life and travelling it is what you make of it.
Ps: it has taken me a while to sign up to TA and write this review but I always intended to as this site has virtually guided me to some lovely places - a tip that fellow travellers I met gave me (in Shela coincidentally) is to compare the reviews made by disaffected travellers across the places they have visited to assess their tendency to whinge ... enough said.