This is actually a question about my '85 MR2. I installed good quality strut inserts when the car had about 60,000 miles on it as the OEM parts had gone pretty soft. The car now has 262,000 miles and I really can't tell if the shocks have gone soft. The old bounce test doesn't really work well. I can get the rear to bounce and it stops dead after one bounce. The front springs are so stiff I can't even compress the suspension to see if it will bounce.

The car feels a bit more loose than it has in the past (I've owned it since new BTW) but geez, it has 262k on the clock, go figure. The new tires I put on a year ago have a pretty soft sidewall, it's hard to find good performance tires anymore in a 185/60-14R size! The tires have good grip but not a very strong turn in feel. Anyway, perhaps part of the softer feel of the suspension I suspect may be worn struts may be the softer riding tires? Strut inserts aren't that expensive anymore, but I'd rather not go through the hassle of changing them if the old ones aren't worn out. But how can I tell with such stiff springs?

Anyone?

Put some new struts in it. You'll feel the difference... I mean, they've got 200K on them!

Try this: Hit a speed hump a decent speed. If it bottoms out, you probably need them. If you feel like you went over it twice, you really need them. If you can't tell, put some new ones on anyway. They've probably been getting progressively weaker since they were 50K old.

I couldn't tell easily on a 2nd gen MR2 I worked on, but I noticed they were leaking. I put new ones on and it made a huge difference in ride quality.

I go over some pretty wicked speed bumps at work every day and it doesn't bottom out or bounce after the initial bump. That's just it, they feel fine in everyday driving but I don't know how they could after 200k on them. Hate to spend money if I don't have to...

Have to?
You can drive on bad struts for a long time. Keep driving on them.

By the time I did the ones on the MR2 I referenced, they had been leaking for so long that all the rubber was totally distorted on the spring insulator. The new ones made so much of an improvement that the owner thought it was a different car (his words) and he owned it since new.
They still weren't to the point where people would point and laugh or flag you down because one wheel is bouncing up and down on the highway even though there's no bumps. Leaking and old as they were, they still had a tad of charge left in them.

From what you say it sounds like the struts are still good. I'm surprised the strut mounts are still good, that is the only time I've replaced my struts when the mounts start to rattle.