Advice on solder flux/paste

[sacentre]

I've been using these low-cost rosin based soldering fluxes for years (see photos) with the traditional 60/40 solder for general electronics assembly - mostly just hobby kits, occasional repair work and recently some smt assembly etc (I haven't yet tried using solder paste with hot air for soldering ICs).

Since I'm about to order a fresh supply, I thought I'd ask first if anyone had any views about "better" alternatives. I see a huge range of prices  for flux pastes and liquids etc. I'm assuming there's a reason for this and wonder if there's anything to be gained from paying more for a different type or brand.

Right now though I've no idea exactly what advantage a "better" flux would offer since my experience is limited - improved flow? cleaner joints? 
Can anyone advise?
TIA

[David Hess]

Some work better than others, but there is no way to know which without testing.

Kester's 44 (now 1544?) flux in liquid and paste is excellent but no longer generally available.

[thm_w]

I don't know about "better" but its more convenient to have the paste flux in a syringe. I use either the generic noclean amtech clones or the MG chemicals paste.
https://mgchemicals.com/products/soldering-supplies/soldering-flux/soldering-flux-paste/
https://www.aliexpress.us/item/4000258887808.html

Big clive mixes up his own liquid version with IPA in a little dropper bottle. Thats probably the cheapest liquid option.

[asmi]

I use this flux: https://www.chipquik.com/store/product_info.php?products_id=310004
Highly recommend, works like charm, and is easy to wash away after soldering!

[tooki]

I've been using these low-cost rosin based soldering fluxes for years (see photos) with the traditional 60/40 solder for general electronics assembly - mostly just hobby kits, occasional repair work and recently some smt assembly etc (I haven't yet tried using solder paste with hot air for soldering ICs).

Since I'm about to order a fresh supply, I thought I'd ask first if anyone had any views about "better" alternatives. I see a huge range of prices  for flux pastes and liquids etc. I'm assuming there's a reason for this and wonder if there's anything to be gained from paying more for a different type or brand.

Right now though I've no idea exactly what advantage a "better" flux would offer since my experience is limited - improved flow? cleaner joints? 
Can anyone advise?
TIA

The Felder flux you show is NOT for electronics! Zinc chloride fluxes are for coarser electrical and mechanical work only. Do not use them on stranded wire.

[wraper]

Good fluxes for electronics never come in tin jars. Either not good or not suitable for electronics at all.

[wraper]

https://www.felder.de/products/metal-construction-industry/soft-soldering/fluxes-for-cu-cu-alloys/loetfett-243100501.html

Flux based on zinc chloride and ammonium chloride with pasty consistency for soft soldering of copper and copper alloys for copper pipe installations, radiator construction, plumbing, dip soldering, fitting manufacturing and other solder works.

And even on pipes you still need to wash it off to avoid corrosion. As of electronics, zinc chloride is nearly impossible to wash off entirely as it penetrates PCB substrate.

[tooki]

Good fluxes for electronics never come in tin jars. Either not good or not suitable for electronics at all.

Yep. Though they used to! (I still have a tin of Kester 44 from the early 1990s.)