ZenMarket is an amazing proxy. The customer service, easy-to-use website, low fees, many credit/shipping options, warehouse storage, and overall reliability is top notch. I've shipped 10 large packages with them after finding them last year, and I've never looked back.
They have a large range of shipping options with full transparency on the pricing which is great for people like me who always seem to get hit in the face with random shipping prices in other companies where they're not as upfront about pricing.
They pack items with great care and I've never once received anything broken even when shipping fragile items. Loads of bubble wrap/packing materials are used to ensure the best care with my items.
The only gripe I have is that it's a wild card on dealing with Y!JA sellers that apparently "don't deal with proxies" despite buying from separate item listings. I guess it a ll depends on the person who reads your unblock request which is understandable.
All in all, I love ZenMarket. No doubt the best and easiest to use proxy I've ever used :)