So I realized this morning that if I get a trainer, I won't know my speed. Then I wondered if it mattered. If not, how to you gauge progress on a trainer?

I always use a computer with rear wheel pickup. Cateye Astrale are cheap and reliable. Garmin also uses rear wheel, many others.

That sounds easy enough. I'd considered that, but thought there was something I must be missing.

Intensity and time matters more but it is okay to see your speed as well. Just don't get hung up on distance as you really aren't going anywhere, as noted by the lack of changing scenery.

Not having power, I'll sometimes do drills on my rollers where I'll keep the speed more or less the same while doing different things with the gears and pedals. Cadence is a must for me, hence the Astrale rec. Also when doing certain intervals, one wants to hold power constant and watch HR variation. Speed on a trainer subs for power as long as resistance is not changed.

So it sounds like a HR monitor might be a good investment?

My goals are to keep or increase my fitness with regard to distance riding. I wouldn't mind getting faster, but my near term goal is a week of 100+ mile days through the hills of Pennsylvania.

I was originally thinking about a fluid trainer (leaning toward the Kurt Kinetic), but then my LBS recommended a Cyclops Pro Mageto trainer. I was wondering if to simulate grinding up hills, that a Cyclops Mag+ might be a less expensive solution that would meet my needs. I'd also considered the Progressive Mag Trainer (I have a trike) Thoughts?

My speed on a trainer is zero. Why do I need to measure it?

This. Duration and level of effort are what matters.

Yes, and unless you have a powertap you have no way to measure improvements or quantify output other than speed. So you really don't know what you're up to. You're just sitting there, hurting yourself.

Oh yes, a HRM is certainly a more important training aid and will increase you speed faster than boutique wheels. So you're riding a recumbent trike? In which case a trainer makes sense. Normally, I recommend a set of rollers with resistance. Kurt Kinetic fluid trainers are the most highly recommended on BF.

If you train for 100 mile hilly rides, you'll get faster if you get after it on the hills. If you train by riding slowly, you get good at riding slow.

It's one of the few metrics I have available without a lot of investment. I figure it's still a step up from the recumbent exercise bike I spend hours and hours on last winter.

Any recommendations on a HRM? I don't need anything fancy.. just something to keep me honest. Cheap and reliable if possible. I've seen bad reviews on almost everyone I've looked at.

Seeing as how the rollers I linked are less expensive, is there an advantage to the Kurt Kinetic?

Is that a long way of saying I get out what I put into it?

I've had very good experiences with several different Polar HRMs over the years.
The Polar FT1 can be had for about $40. I'd go with the FT4 for about $80, because of the buttons. Amazon probably has the best prices.

Users say the feel of the KK is very like the road. It has a chart that will give you power readings.

Not everyone wants to get faster, or so they say.