Pair of iittala Festivo candlesticks

I found a pair of Festivo candlesticks by iittala. No "TS" engraving but they do have a manufacture sticker.
For anyone who collects these candlesticks, do you notice a quality difference between the "TS" marked ones and the ones not marked? I feel like the "TS" ones are heaver and are better quality in general. The non inscribed ones by iittala are a bit sloppy. The glass mold seams are more visible and the feel light.