You'll always get bazillion different responses to a question like you've posed. I agree that the absolute best way to go is to contact Mike Lewis of Lewis Racing (aka "Wolfplace" on here ) for one of the best built custom engines that money can buy. I understand the attraction of the sales pitches of crate engines and the companies that sell them. I bought a World Products engine and also had some problems which caused me to send the engine back.
Keep in mind when you sift through the positive and negative comments on crate engines, that World offers both bare blocks, short blocks, and complete engines. There are a number of guys here who have used World blocks and heads, and have been pleased with them as long as they assembled their engines themselves, or had a local machine shop do the assembly. If anything about World Products engines is in question, it's their assembly practices.
That isn't to say that there haven't ever been any machining practices at World that are questionable, but I've heard both positive and negative comments about many crate engine companies including Shafiroff. So it's often a crap shoot when you buy an engine already assembled, unless you take your business to guys like "Wolfplace". I haven't been a customer of his (yet) but I've never heard anything bad about him nor about his engines.
Many guys here will tell you that doing biz with your local engine builder is the best way to go, and I believe that many times that's true, but I've also heard horror stories from guys who have chosen that route too. I've even heard some bad stories about GM crate engines. Not to mention they seem to be lacking in power.
I've never heard anything bad about Reher Morrison crate engines, but their focus seems to be more on all-out race engines rather than steetable pump gas ones. One look at their posted dyno sheets on their website which all begin a 5,000+ RPM from what I've seen will tell you that.
My conclusion from my own experience so far is that it's hit or miss when you deal with almost all aftermarket companies. And if you're lucky, you'll find one that turns out to be different than most others. Good luck.