Best way to assess the bottom end condition?
 

I'm just about to pull the trigger on a top end rebuild for my street car at a local reputable Porsche shop. 160k and goes through lots of oil (300-400 miles per qt). Still runs strong and no odd noises. Typical valve guide wear.

I'm trying to stay somewhat on a budget so I really don't want to mess with the bottom end. It's my street / occasional track day car but I'm not looking for ultimate performance. Runs really good so I see no reason to mess with the bottom end. Would really like to keep the "while you're in there" to a minimum. Not trying to be cheap, just realistic in what I want out of the engine. Everyone says 250-300k on the bottom end is totally reasonable.

What is the best way to evaluate it's condition?
Does a leakdown and compression test tell it all?
What are the telltale signs your bottom end needs work?
Is re-ringing it a no-brainer thing you should go ahead and do regardless?

Definitely re -ring for sure they become brittle. If there's no noise (knocking) or leaking I wouldn't split the case. The one concern I have would be the timing chain stretch and cam and idler gears at that mileage.

It is a slippery slope of "while I am in there" that I just slid down.

Once the pistons are off to re-ring it you are looking at a "just a few more bolts" to split the case and do it right.

My engine had 150,000 miles of fun on it. We split the case.

I am real glad I did. KNOWING that I have new chains, new sprockets, ramps and the like is comforting. I found one rod bearing with a hot spot of wear. Nothing real bad but it was enough to make me feel justified in the additional expense. The intermediated shaft bearing had the most wear. All the bearings were just replaced with new bearing at stock spec.

I new have new Racewear rod bolts and case bolts.

It really all comes down to how long do you expect to own that car. If like me you plan to own forever spend the money and do it right. If you see changing to a newer car soon, do top end and hope that is all it needed.

Oil Pressure will tell you a lot.