When my 41 started getting flaky, I picked up a 33S on clearance at Walmart. I was pleased to find it approved for FE and PE exams, and so is the 35S. I saw a review somewhere else regarding the displays. The 35S is definitely clearer, because the pixels are spread out -- the decimal point is easier to find, etc. The keys on the 35S feel much better than on the 33S, the Enter key is back where it belongs, and the rows are straight instead of the weird chevron of the 33S -- What were they thinking? Still checking it out, the 35S has a cool way to quickly program a repetitive calculation. I am looking forward to transferring my 41 programs to the 35S.

Hi, I am a RPN calculator user for 10 years and just can't convince myself to return to conventional algebraic calculators. When I saw the HP 35s, I was convince by its classic design and because it was not a graphic calculator. I just love this calculator and I haven't nothing to say about its functionnalities, it just perfect for me. I'm a mechanical engineer and use it each day. However I had it for two years now and my Enter key is broken (it stands loose in its cavity and it doesn't punch each time I try, see pictures). Previously I had an HP 48gII that did the same thing, it begin by the Enter key followed by the number keys and after a time it is not praticle to work with. With this 48gII this defect appeared just after the end of the warranty, I wrote to HP and they changed it anyway (Excellent work). The 48gII that they sent me broke within a year (see pictures, less good design). And now my HP35s begin to have the same problem. Don't mislead me I am not hard on material. I'm a consulting engineer and my calculators always stays on my desk and don't follow me on the field. Also read, and you'll find other critics talking about those key problems. So I would not recommend this product it will just get you addict to the RPN, but the quality is not there anymore. Hope they will correct this problem a day and come back to the quality that was associated with there calculators.