What are the roaming implications for UK or US SIM card users in Lithuania, and how does DataESIM compare?

For UK or US SIM card users, roaming in Lithuania typically incurs significant charges. While Lithuania is within the EU, post-Brexit, most UK carriers (e.g., O2, Vodafone UK) have reinstated daily roaming fees, often ranging from £2-£6. US carriers (e.g., AT&T, Verizon, T-Mobile US) generally offer expensive international day passes ($10-$15/day) or per-MB rates. DataESIM provides a cost-effective, high-data alternative, eliminating unpredictable roaming bills and offering transparent, fixed-cost connectivity specifically optimized for heavy data usage in Lithuania.