Currently using ubercart and things working smoothly overall.

Situation: ending up having multiple domains(5-10) each with products to buy. Products range from file downloads to recurring subscription products.

Problem: this is becoming very upkeep intensive

Desire: have a central "payment site" that the shopping cart is on. All of my websites would have the products services, etc (or at least links to the products). I'm not explaining this well, but it is how 1shoppingcart is setup.

If what I have attempted to explain above makes sense to anybody, I'm curious to hear any solutions you have or may be thinking of.