Apologies for those who saw this hand on another thread which was more of a "what do you think of my play here." I'm just using it as an example and don't want to focus on the hand itself. . . I'd really like to hear general thoughts on this question:
How do you judge if you are getting good enough odds to call a raise with SCs (or small PPs) when you expect a many to see the flop?

In this hand, I figured I was getting good enough odds to call the pfr but only by gut feeling. I figured I'd have 3-4 opponents each with effective stacks of 10-20x the raise. Heads up or 3 way, I'll use 5/10 rule for PP and 4/8 for SCs. Are these ratios still applicable to 2 opponents? How do you judge for 3-4 opponents?

This table: To my right three college aged, online poker junkie young gun types (all have stacks of $200-$300). To my left are several calling stations . . . one to my immediate left is an ATM ($300). Only other player of note is an older Asian man to the left of the calling stations ($750) who is mainly focused on playing the ATM.

I have JTs UTG and limp. All but one limp to a young gun on the button who raises to $20. Another young gun in SB calls. I figure the ATM will call, the older Asian guy and maybe 1-2 more, so I call figuring I'm getting the odds necessary to see the flop. ATM and older Asian guy call, all others fold, we go to flop five handed.

One problem I see with this setup is that you are probably not going to get good odds to draw when you flop a draw. I like playing connectors when the stacks are much deeper, in position, when the likely flop bettor can often make the mistake of betting so small on the flop that I can get good odds. In this spot you might end up just playing with the young guns, who will deny an easy call with a draw. So you have to hit huge. Or you get everyone in and the flop pot is so bloated that you are going to have a tough decision with a draw, the bets will be large with little behind.

I don't really look for a mathmatical rule here, and in this spot I think you are close to the neutral EV line, depending on the likelyhood of opponents mistakes.

My room is a 150bb buyin, once stacks start getting $450ish I start getting horny for suited connectors. At the depth you are playing here, oop, I can pass playing this to a raise with competent players involved.

^That. Also position is very important if you want to get max value post flop and you limp calling that raise makes your hand look like exactly what it is, so its very unlikely anyone even close to decent will pay you off without a cooler scenario

I would agree and I think that open limping SCs dramatically decreases their value, even if you are getting odds in accordance to the 4/8 rule. If I'm limping these it's only behind other limpers and with relatively good position. It sucks being OOP, not sure whether your draw is any good based on other people in the hand holding the nut draw and having to put in a ton of money to fold out other draws and risk running into a big made hand at the same time.

To be honest I think the relative value of suited connectors and non suited connectors shift in live play versus online (or higher live limits). Online you are not playing with so many people to the flop and you can be far less concerned about higher flushes. Live players play more suited hands and will go deeper with them. So your RIO go up with the suited aspect of your hand.

Unsuited connectors do not suffer this drawback to the same extent. I am quite happy to play unsuited connectors in far more spots live than I would attempt online and, of course, there are far more of them to play.

Like others have said here, position is key with these hands even when getting good odds.

However, you can make exceptions.
It depends 1)on how bad your opponents are and if they'll go too far postflop even if they have position.
2) how good you are at playing OOP. Be careful here cause if every poker player was polled they'd vote "yeah, I can play great OOP" when we know that the vast majority fail here.

IMO if you play these OOP, even with good odds, the biggest danger is when we flop "kind of a good hand", like J84 when we have JTs. We bet it or call bets on mult streets being trapped by seemingly good odds to continue and put a large amount in postflop only to miss/hit but someone hits bigger/lose to AJ.

I guess I have to respectably disagree with you here. IMO the value of SC are the draws that they flop, not the made hands that they flop, and the draws are way higher w/SC vs unsuited connectors. Also it seems that you're saying SC can run into a bigger flush(RIO) but of course unsuited connectors still run into 3 flush boards which is still worse, right?
A problem I have w/unsuited connectors is there are so many of them dealt out(as you mentioned) and if I play these my # of hands played gets too high. I've pretty much dropped playing unsuited connectors (live) JT and lower and it seems to improve my play. Tho I'm still experimenting with this, it's hard to tell for sure live.