I've had 3 builds with Spongebob, and for my 50 cents worth... I'd never do it again.
Builds are fine, but if you have any problems... it's almost like you're shit out of luck.
That said, credit to him, he did fix my issue by sending a new movement, but I had to badger and pester him over the course of 5-6 months, a message once or twice a week... eventually he dispatched the part and hey-presto, I sent it to a UK modder reputable here and was fixed within 2 days...
But the whole experience ruined the watch, it's why I sold my 5711. It worked perfectly, but the whole experience was tainted. What should have been an easy 2-3 months.... was a nightmare 8+ months. In the end I sold it on here... and lost some money but was happy to be rid of it. (It worked perfectly and new owner was very happy)
I'm not the type of person to message someone daily, or expect a reply within a few hours even... but when you've sent a message and he hasn't even read it on whatsapp in 2 weeks you start to feel a bit ignored.
He never scammed me and in the end I got everything I paid for. However, it was a complete ball ache and I will never repeat that again.
I couldn't possibly in good conscious recommend him to anyone purely because of the aggravation, it isn't worth the grey hairs!
I doubt he's scammed you, he's a good guy, but zero points for communication, that said your timescales are quite excessive.