This is another thorny subject. It's hard to buy a "bad" fly reel. The competition simply doe not permit that to happen. On the other hand, it certainly is possible to pay more than the reel is really worth ... I say that hoping you will understand I speak from experience since I own somewhere around 50 fly reels.
If you were here with me, I would lay them out and let you do a hands-on comparison of the pros and cons of each But you are not here ... so let's look at what The Full Creel stocks. I am not familiar with the Harris or Echo reels but the remainder I have either thrown or own. For example, I own three of STH/Cortland high end Turbines that I love. I also bought into STH's high end cassette concept with two salt-capable reels and bunches of cassettes. My FlyLogic Optimum has done nothinbg but hard works without a peep. The G. Loomis Synchrotech is a fine reel made, the last I heard, by the Waterworks.
Any of these reels have differences - pro & con- and, yes, I feel blessed to have had these experiences with so many great products. The best reel for the money I ever owned was the Mastery series by Scientific Anglers: fantastic drag, great weight to capacity ratio, and tough. Unfortunately, they were not pretty. Some MBA made the mistake of finishing them in a dull black as opposed Abel's Gloss. It made no difference that they were of solid bar aluminum -- the dull black finish suggested to folks that they were cast. Sad to say they are gone from the market.
Here are a couple of thoughts that might help you. (1) the cost of the reel isn't necessarily the biggest expernse; consider the price of spare spools and it's my guess that you will need two. A spare for an Abel costs about 2/3 of the cost of the reel itself. My bank account has never allowed me to say, "And let me have an additional 4 spools along with that Abel." Instead, my approach has been to backup my primary reel with a second reel like the STH Cassette ... changing out lines on the water is not my bag. Salt can do some funny things, particularily with all the holes being drilled into the reel's frame these days. If something can go wrong, it will! (2) Even if you spring for the expense of extra spools, if the reel, itself, goes down the apare spools will be of little comfort.
You can mitigate the difficulties of changing lines in mid-stream by going with shooting heads ... when you switch out, you deal with about 30-feet og line, or less, as opposed to lengths of 90 to 105-feet. I did a series on the shooters that includes a couple of the multi-tip lines now available. Hard to go wrong with any of these.
As for Cortland? They build excellent lines and are now surging with the new 444 Classic Sylk, the 444 Preciskion Taper, and the 555 Hi-Floating Dyna-Tip. Sci-Anglers is also great. My personal opinion is that SA had the lead with AST and are now tied ... It's sort of like Ford & Chevy. My favorite line for almost anything in the heavier weights is/was the SA Bonefish -- didn't make any difference to me or the largemouth bass I was after. However, I recently reviewed both the Sylk and the 444 Precision and I must confess that for my casting stroke, the Sylk is my personal choice for freshwater.
Hope this helps in making a decision...
PS. If you buy both rod and reel from Steve, twist his arm for both a line and backing...