A great alternative for instant feedback on a speed run is to use a cheap android phone with GPS-Logit installed.
Put it in a waterproof arm bag, wear it on your bicep.
listen to you speed every second with the speed-talk function. No need to look at anything.
An even better solution that Mark Jordan uses, is to strap the phone bag to the side of his helmet to make the speed-talk very easy to hear under all circumstances.

Cheap Andriod phones are very convenient and powerful little computers with a lot of features that would be much more difficult and expensive to build into a EPS type of device. There are some great possibilities for combining the two.
Many years ago (2015) Manfred Fuchs made me a small Bluetooth GPS logger with a Ublox M8 that transmits its data output to a cheap android phone running GPS-Logit. The phone does all the processing, recording and gives me running results in the GPS windsurfing categories AND talks my current speed in real time.

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The downside is that the phones are not waterproof and need to be protected in a good waterproof arm bag, and you are now dealing with two parts for the system, the BT logger (I always wear it in my helmet) and the phone (on my arm). It is more convenient to use a single ESP or LCD Motion, but neither can do the speed talk.
Nowadays, I use the Motion for the results and use the phone for the audio feedback from its own internal GPS. The phone (using its internal GPS) is not always very accurate (some times it is way off!!

) but is usually 'close enough' for useful audio feedback.

So, what I am suggesting is that it would be interesting to include a speaker and speed talk in an ESP type device for Audio feedback.