The simplest way to look at this is, do you have a budget? If not then go for it If your budget is cutting it close, don't even start.
My engine died last month, and I instantly thought, time for a V8. Priced it all up, just wasn't worth it. So much easier and cheaper in the states.
If I had money, I'd do it without a second thought, but it's a costly project, where you need to budget for the unexpected as well as the expected.