Thanks RP. Great to be able to learn from a Giottos user.
Since I wrote the original question, I have sold the Velbon equipment and bought the MT-7371 & MH-3300 combination, with the MH-658 QRA. I am most pleased with it, except it is too heavy to carry any distance (I estimate 3.6 kg or almost 8 lbs).
I decided to see if I could get a Giottos leg set and ball head that is significantly lighter, but at least 153cm (60") tall without the centre column being extended (this measurement is the total of the ball head and the leg set), Arca Swiss compatible and reasonably priced.
I don't mind if the Giottos QRA limits me to inserting some brands of plates only from the top, as I plan to use Giottos plates and their VR bracket (I already have these), and if I got some other brands in the future, I would simply mount them from the top, like you do ...
So the following is the summary of choices if i stay with Giottos:
My Baseline: MT-7371 & MH-3300/MH-658 (what I have now) 72" tall (I need 60") & 7.9 lb
MT-9260 & MH-1300/MH-657 ($280 to buy) 60" tall & 6.2 lb (32 ounces less)
MT-7371 & MH-1300/MH-657 ($140 to buy) 71" tall & 7.3 lb (~10 ounces saved)
MT-7371 & MH-1301/MH-656 ($130 to buy) 68" tall & 6.8 lb (~17 ounces saved)
MT-7271 & MH-1301/MH-656 ($410 to buy) 63" tall & 5.9 lb (27 ounces saved)
Since I am also buying a 50D in a day or two, to replace my XTi, the first and last choices are out, for financial reasons.
My next step is to investigate the Flashpoint heads, SLIK leg sets, and compare combinations of them to this data. My aim will be to save more weight, keep the minimum height I need, and spend a reasobale amount. It looks like the MT-7371 legs are just too heavy, and I fear I may have to buy another leg set, sacrificing some height to get the weight down substantially.
Maxdave
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