Good question, and the answer is........it depends!! lol.
When making gearing choices, you'd be wise to take into account a few variables:
1) Scooter type/weight - full body series 2, or cutdown GP on vega leggies?
2) Your type/weight - 6'6" tall and 22 stone, or 5'2" and 8 stone?
3) Riding type/style - solo riding with no luggage and only a few hills where you live, or two's up loaded with luggage going uphill into a headwind?
4) Type of tune on the cylinder, with what pipe and carb - Standard TS1 with 35mmTMX and JL4, or touring tune to cylinder with JL3, 30mm Delly and a variable ign kit?
And so on........
On 'average' (if there is such a thing!) i'd say TS1's will fall between 4.8 and 5.2 for MOST users. But 4.25-4.60 can be achieved with the right combination. eg - TS1 with 'touring tune' to cylinder, 30mm carb, ADS touring pipe. A full bodied series 3 with a solo rider and no luggage will pull those areas of gearing (4.2-4.6) easily, but a tall-fat bloke, with fat wife and luggage on board might struggle a bit on such combinations and need to be looking at the 4.8-5.2 options instead.