Rather than limit the type of computer you need by the size of display, why
not look at having a pair of small reading lenses added to the lower part of
your mask lens?

This would then allow you to properly read all of your gauges and equipment.
There are many companies that can offer this type of product at a reasonable
cost.   If you only require a low dioptre of correction for normal reading
glasses, this will be even less underwater due to the magnifying properties
of water (things appear approximately 30% larger underwater).

Don't compromise on your equipment, resolve the underlying issue.

If you still want a large display then the Uwatec / Scubapro range of
computers (previously sold as Aladdin) seem to offer the largest sized
displays.

I tested one as we got one sent to the last place I worked as a spare
general use computer. It's alright, and the calculations seem pretty
average (didn't do any deco testing as it was going to be a purely
no-stop diving comp. The display was reasonable, although I still much
prefer the Suunto displays (I have a Vyper as my main general use
computer).

Battery life wise, it was alright - no issues although again, the vyper
battery isn't much more difficult to change, is widely available (it's
a medical battery) and the last one got me through 300+ dives.

I might sound like I'm trying to sell Suunto, but from personal
experience (Aladdin, Mares, Buddy, Oceanic, Suunto) they are the my
overall general purpose favourites in usability and durability.

I have never used the Mares M1 myself, but a diving buddy (who wears glasses) said the M1 is not  more or less difficult to read than most other computers. He has a prescription mask, which helps. If you are concerned about seeing the display, a computer with a larger display is worth the peace of mind. You could also see if there's a shop where you can rent one & try it out before buying.

Cheers,
Ian
associate editor, http://www.thescubaguide.com/

 I've researched dive computers on www.ScubaDiving.com and the Mares M1 RGBM looks like a "best buy" to me. The concern I have is the readability of the text and icons on the display. They look rather small to me and since I'm over 40 and my eyes aren't what they used to be (I use reading glasses), I'm concerned that they might not be very readable, especially at depth. Can any owners comment on this issue, or offer any other feedback on this computer? Thanks in advance for any help!

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